CVE-2023-53356 usb: gadget: u_serial: Add null pointer check in gserial_suspend

What is CVE-2023-53356?

CVE-2023-53356 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: u_serial: Add null pointer check in gserial_suspend

Consider a case where gserial_disconnect has already cleared gser->ioport. And if gserial_suspend gets called afterwards, it will lead to accessing of gser->ioport and thus causing null pointer dereference.

Avoid this by adding a null pointer check. Added a static spinlock to prevent gser->ioport from becoming null after the newly added null pointer check.

Weakness: CWE-476

Which versions are affected by CVE-2023-53356?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53356?

Apply the vendor's patch.

Is CVE-2023-53356 being exploited?

There is no known exploitation of CVE-2023-53356 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-53356, DEBIAN-CVE-2023-53356, GHSA-fvf2-2vh9-p4j4, UBUNTU-CVE-2023-53356.